The Experts below are selected from a list of 1821 Experts worldwide ranked by ideXlab platform
G. Kahlmeter - One of the best experts on this subject based on the ideXlab platform.
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standard and real time multiplex pcr methods for detection of Trimethoprim Resistance dfr genes in large collections of bacteria
Clinical Microbiology and Infection, 2007Co-Authors: Malin Grape, A. Motakefi, S. Pavuluri, G. KahlmeterAbstract:Two multiplex PCR (mPCR) methods were developed to screen large collections of Trimethoprim-resistant Escherichia coli isolates for the most prevalent Resistance determinants. Five common integron-carried genes (dfrA1, dfrA5, dfrA7, dfrA12 and dfrA17) were selected as PCR targets. Primers and conditions for standard mPCRs and real-time mPCRs were selected and tested. Two protocols using essentially the same primer pairs were established. The standard mPCR protocol also included an internal control targeting the E. coli 16S rRNA gene. Both protocols proved to be sensitive and specific for detection of the five selected genes. Screening of three different collections of clinical urinary and blood isolates (n = 368) with the two multiplex methods revealed that the five dfr genes accounted for 75-86% of Trimethoprim Resistance. The standard mPCR is useful and accessible for most laboratories, while the real-time mPCR requires additional equipment and expensive reagents, but is very convenient for high-throughput screening of large collections of bacterial isolates.
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Standard and real‐time multiplex PCR methods for detection of Trimethoprim Resistance dfr genes in large collections of bacteria
Clinical Microbiology and Infection, 2007Co-Authors: Malin Grape, A. Motakefi, S. Pavuluri, G. KahlmeterAbstract:Two multiplex PCR (mPCR) methods were developed to screen large collections of Trimethoprim-resistant Escherichia coli isolates for the most prevalent Resistance determinants. Five common integron-carried genes (dfrA1, dfrA5, dfrA7, dfrA12 and dfrA17) were selected as PCR targets. Primers and conditions for standard mPCRs and real-time mPCRs were selected and tested. Two protocols using essentially the same primer pairs were established. The standard mPCR protocol also included an internal control targeting the E. coli 16S rRNA gene. Both protocols proved to be sensitive and specific for detection of the five selected genes. Screening of three different collections of clinical urinary and blood isolates (n = 368) with the two multiplex methods revealed that the five dfr genes accounted for 75-86% of Trimethoprim Resistance. The standard mPCR is useful and accessible for most laboratories, while the real-time mPCR requires additional equipment and expensive reagents, but is very convenient for high-throughput screening of large collections of bacterial isolates.
Stefan Schwarz - One of the best experts on this subject based on the ideXlab platform.
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First Detection of the Staphylococcal Trimethoprim Resistance Gene dfrK and the dfrK-Carrying Transposon Tn559 in Enterococci
Microbial Drug Resistance, 2012Co-Authors: María López, Stefan Schwarz, Kristina Kadlec, Carmen TorresAbstract:The Trimethoprim Resistance gene dfrK has been recently described in Staphylococcus aureus, but so far has not been found in other bacteria. A total of 166 enterococci of different species (E. faecium, E. faecalis, E. hirae, E. durans, E. gallinarum, and E. casseliflavus) and origins (food, clinical diseases in humans, healthy humans or animals, and sewage) were studied for their susceptibility to Trimethoprim as determined by agar dilution (European Committee on Antimicrobial Susceptibility Testing) and the presence of (a) the dfrK gene and its genetic environment and (b) other dfr genes. The dfrK gene was detected in 49% of the enterococci (64% and 42% of isolates with minimum inhibitory concentrations of ≥2 mg/L or ≤1 mg/L, respectively). The tet(L)-dfrK linkage was detected in 21% of dfrK-positive enterococci. The chromosomal location of the dfrK gene was identified in one E. faecium isolate in which the dfrK was not linked to tet(L) gene but was part of a Tn559 element, which was integrated in the ch...
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Molecular Basis of Sulfonamide and Trimethoprim Resistance in Fish-Pathogenic Aeromonas Isolates
Applied and Environmental Microbiology, 2011Co-Authors: Kristina Kadlec, Ellen Von Czapiewski, Heike Kaspar, Jürgen Wallmann, Geovana Brenner Michael, Ulrike Steinacker, Stefan SchwarzAbstract:Sulfonamide-Trimethoprim-resistant Aeromonas salmonicida and motile Aeromonas spp. from diseased fish of the GERM-Vet study carried the sul1 gene together with mostly cassette-borne Trimethoprim Resistance genes, including the novel gene dfrA28. The seven dfrA and dfrB genes identified were located mostly in class 1 integrons which commonly harbored other gene cassettes.
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identification of a novel Trimethoprim Resistance gene dfrk in a methicillin resistant staphylococcus aureus st398 strain and its physical linkage to the tetracycline Resistance gene tet l
Antimicrobial Agents and Chemotherapy, 2009Co-Authors: Kristina Kadlec, Stefan SchwarzAbstract:A novel Trimethoprim Resistance gene, designated dfrK, was detected in close proximity to the tetracycline Resistance gene tet(L) on the ca. 40-kb plasmid pKKS2187 in a porcine methicillin (meticillin)-resistant Staphylococcus aureus isolate of sequence type 398. The dfrK gene encodes a 163-amino-acid dihydrofolate reductase that differs from all so-far-known dihydrofolate reductases.
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dfrA20, a Novel Trimethoprim Resistance Gene from Pasteurella multocida
Antimicrobial Agents and Chemotherapy, 2005Co-Authors: Corinna Kehrenberg, Stefan SchwarzAbstract:A novel Trimethoprim Resistance gene, designated dfrA20, was detected on the 11-kb plasmid pCCK154 from Pasteurella multocida. The dfrA20 gene codes for a dihydrofolate reductase of 169 amino acids. Sequence comparisons revealed that the DfrA20 protein differed distinctly from all dihydrofolate reductases known so far.
S. Pavuluri - One of the best experts on this subject based on the ideXlab platform.
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standard and real time multiplex pcr methods for detection of Trimethoprim Resistance dfr genes in large collections of bacteria
Clinical Microbiology and Infection, 2007Co-Authors: Malin Grape, A. Motakefi, S. Pavuluri, G. KahlmeterAbstract:Two multiplex PCR (mPCR) methods were developed to screen large collections of Trimethoprim-resistant Escherichia coli isolates for the most prevalent Resistance determinants. Five common integron-carried genes (dfrA1, dfrA5, dfrA7, dfrA12 and dfrA17) were selected as PCR targets. Primers and conditions for standard mPCRs and real-time mPCRs were selected and tested. Two protocols using essentially the same primer pairs were established. The standard mPCR protocol also included an internal control targeting the E. coli 16S rRNA gene. Both protocols proved to be sensitive and specific for detection of the five selected genes. Screening of three different collections of clinical urinary and blood isolates (n = 368) with the two multiplex methods revealed that the five dfr genes accounted for 75-86% of Trimethoprim Resistance. The standard mPCR is useful and accessible for most laboratories, while the real-time mPCR requires additional equipment and expensive reagents, but is very convenient for high-throughput screening of large collections of bacterial isolates.
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Standard and real‐time multiplex PCR methods for detection of Trimethoprim Resistance dfr genes in large collections of bacteria
Clinical Microbiology and Infection, 2007Co-Authors: Malin Grape, A. Motakefi, S. Pavuluri, G. KahlmeterAbstract:Two multiplex PCR (mPCR) methods were developed to screen large collections of Trimethoprim-resistant Escherichia coli isolates for the most prevalent Resistance determinants. Five common integron-carried genes (dfrA1, dfrA5, dfrA7, dfrA12 and dfrA17) were selected as PCR targets. Primers and conditions for standard mPCRs and real-time mPCRs were selected and tested. Two protocols using essentially the same primer pairs were established. The standard mPCR protocol also included an internal control targeting the E. coli 16S rRNA gene. Both protocols proved to be sensitive and specific for detection of the five selected genes. Screening of three different collections of clinical urinary and blood isolates (n = 368) with the two multiplex methods revealed that the five dfr genes accounted for 75-86% of Trimethoprim Resistance. The standard mPCR is useful and accessible for most laboratories, while the real-time mPCR requires additional equipment and expensive reagents, but is very convenient for high-throughput screening of large collections of bacterial isolates.
Shui-feng Chang - One of the best experts on this subject based on the ideXlab platform.
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Two new gene cassettes, dfr17 (for Trimethoprim Resistance) and aadA4 (for spectinomycin/streptomycin Resistance), inserted in an Escherichia coli class 1 integron
Journal of Antimicrobial Chemotherapy, 2000Co-Authors: Chung-yu Chang, Lin-li Chang, Yu-hung Chang, Tsong-ming Lee, Shui-feng ChangAbstract:Two new gene cassettes, dfr17 and aadA4, inserted in a class 1 integron of Escherichia coli EC107, are described here. The dfr17 cassette encodes Trimethoprim Resistance and has 91% identity with the dfrVII dihydrofolate reductase gene. The aadA4 cassette confers Resistance to spectinomycin and streptomycin and shows 94% identity with the aadA3 gene. The integron carrying the dfr17 and aadA4 cassettes was located on a conjugative plasmid, pEC1072.
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two new gene cassettes dfr17 for Trimethoprim Resistance and aada4 for spectinomycin streptomycin Resistance inserted in an escherichia coli class 1 integron
Journal of Antimicrobial Chemotherapy, 2000Co-Authors: Chung-yu Chang, Lin-li Chang, Yu-hung Chang, Tsong-ming Lee, Shui-feng ChangAbstract:Two new gene cassettes, dfr17 and aadA4, inserted in a class 1 integron of Escherichia coli EC107, are described here. The dfr17 cassette encodes Trimethoprim Resistance and has 91% identity with the dfrVII dihydrofolate reductase gene. The aadA4 cassette confers Resistance to spectinomycin and streptomycin and shows 94% identity with the aadA3 gene. The integron carrying the dfr17 and aadA4 cassettes was located on a conjugative plasmid, pEC1072.
Kristina Kadlec - One of the best experts on this subject based on the ideXlab platform.
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First Detection of the Staphylococcal Trimethoprim Resistance Gene dfrK and the dfrK-Carrying Transposon Tn559 in Enterococci
Microbial Drug Resistance, 2012Co-Authors: María López, Stefan Schwarz, Kristina Kadlec, Carmen TorresAbstract:The Trimethoprim Resistance gene dfrK has been recently described in Staphylococcus aureus, but so far has not been found in other bacteria. A total of 166 enterococci of different species (E. faecium, E. faecalis, E. hirae, E. durans, E. gallinarum, and E. casseliflavus) and origins (food, clinical diseases in humans, healthy humans or animals, and sewage) were studied for their susceptibility to Trimethoprim as determined by agar dilution (European Committee on Antimicrobial Susceptibility Testing) and the presence of (a) the dfrK gene and its genetic environment and (b) other dfr genes. The dfrK gene was detected in 49% of the enterococci (64% and 42% of isolates with minimum inhibitory concentrations of ≥2 mg/L or ≤1 mg/L, respectively). The tet(L)-dfrK linkage was detected in 21% of dfrK-positive enterococci. The chromosomal location of the dfrK gene was identified in one E. faecium isolate in which the dfrK was not linked to tet(L) gene but was part of a Tn559 element, which was integrated in the ch...
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Molecular Basis of Sulfonamide and Trimethoprim Resistance in Fish-Pathogenic Aeromonas Isolates
Applied and Environmental Microbiology, 2011Co-Authors: Kristina Kadlec, Ellen Von Czapiewski, Heike Kaspar, Jürgen Wallmann, Geovana Brenner Michael, Ulrike Steinacker, Stefan SchwarzAbstract:Sulfonamide-Trimethoprim-resistant Aeromonas salmonicida and motile Aeromonas spp. from diseased fish of the GERM-Vet study carried the sul1 gene together with mostly cassette-borne Trimethoprim Resistance genes, including the novel gene dfrA28. The seven dfrA and dfrB genes identified were located mostly in class 1 integrons which commonly harbored other gene cassettes.
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identification of a novel Trimethoprim Resistance gene dfrk in a methicillin resistant staphylococcus aureus st398 strain and its physical linkage to the tetracycline Resistance gene tet l
Antimicrobial Agents and Chemotherapy, 2009Co-Authors: Kristina Kadlec, Stefan SchwarzAbstract:A novel Trimethoprim Resistance gene, designated dfrK, was detected in close proximity to the tetracycline Resistance gene tet(L) on the ca. 40-kb plasmid pKKS2187 in a porcine methicillin (meticillin)-resistant Staphylococcus aureus isolate of sequence type 398. The dfrK gene encodes a 163-amino-acid dihydrofolate reductase that differs from all so-far-known dihydrofolate reductases.
